A tracheal cannula of the invention includes a breathing path for supplying and discharging air formed between a basal end for connection with a breathing tube extending from an external artificial respirator and a distal end for insertion into a patient's trachea, and a trachea side opening formed at the distal end of the breathing path. Besides and along the breathing path, a suction path is provided for sucking phlegm accumulated in the patient's trachea. A phlegm suction opening is formed in a region of a wall of the suction path on the side of the inner wall of the trachea between the distal end of the breathing path and a cuff, the phlegm suction opening facing the inner wall of the trachea.